TITLE:   GCN CIRCULAR
NUMBER:  37336
SUBJECT: GRB 240825A: further SAO RAS optical observations
DATE:    24/08/29 09:58:26 GMT
FROM:    Moskvitin Alexander at SAO RAS <mosk@sao.ru>

A. S. Moskvitin and O. I. Spiridonova (SAO RAS)
report on behalf of the GRB follow-up team.

We observed the field of the GRB 240825A (The Fermi GBM team,
GCN 37273; Gupta et al., GCN 37274; Lalla et al., GCN 37288;
Evans et al., 37290; Gropp et al., GCN 37294; Joshi et al.,
GCN 37298; Sharma et al., GCN 37301; Frederiks et al., GCN 37302;
Wang and Xiong, GCN 37315) with the SAO RAS 1-meter telescope
Zeiss-1000 equipped with the CCD-photometer and UBVRcIc filters.
We obtained 18 x 300 sec. images with Rc filter on August 28,
19:17:07 -- 21:04:35 UT (t_mid - T0 = 3.1791 days).

The OT (Gupta et al., GCN 37274; Jiang et al., GCN 37275;
Dutton et al., GCN 37276; Odeh and Guessoum, GCNs 37277, 37299;
Zhang et al., GCN 37278; Li et al., GCN 37280; Izzo and Malesani,
GCN 37287; Lipunov et al., GCN 37289; Leonini et al., GCN 37291;
Wu et al., GCN 37292; Martin-Carrillo et al., GCN 37293;
Brivio et al., GCN 37295; Kuin et al., GCN 37296; Le Floc’h et al.,
GCN 37300; Zheng and Filippenko, GCN 37304; Wang et al., GCN 37306;
Maksut et al., GCN 37307; Melandri et al., GCN 37310;
Romanov, GCN 37335) is clearly detected in the stacked frame
with the brightness of R = 22.15 +/- 0.07 calibrated against
nearby Pan-STARRS stars (magnitudes converted to R band)
and not corrected for the MW extinction.